Extended State Observer Based Adaptive Backstepping Nonsingular Fast Terminal Sliding-mode Control for Robotic Manipulators with Uncertainties.

This paper proposes a novel robust finite-time tracking control scheme for robotic manipulators with uncertainties and external disturbances. In order to reduce the chattering phenomenon and enhance the robustness of the system, we design a novel extended state observer with filter function for estimating the lumped term of system uncertainties and external disturbances. We adopt the backstepping mechanism to design an adaptive backstepping nonsingular fast terminal sliding mode controller, achieve finite time convergence of the tracking errors while avoiding the singularity problem. An adaptive update law is designed for the switching gain, which further weakens the chattering problem. The finite-time convergence of tracking errors and the stability of the closed-loop system are ensured by the Lyapunov criterion. In comparison with other control methods, numerical simulation on a two-link rigid robot manipulator demonstrates the effectiveness and superiority of the proposed method. [ABSTRACT FROM AUTHOR]